1. Field of the Invention
Embodiments of the present invention generally relate to server networks and, more particularly, to creating a replica database in a target server.
2. Description of the Related Art
In an effort to protect computer data from catastrophic failure of a computer or storage volume, data has traditionally been backed up from a primary storage device to a secondary storage device. The backup process and, when needed, the restoration process can be time consuming. In modern computing environments, failure of a computer or storage system requires an instantaneous transition to the backed up data. Transactions cannot be stopped to wait for a restoration process. As such, redundant critical systems are used that contain replicated data.
A primary system (referred to herein as a source server), for example, a database system, will copy its data to a redundant system (referred to herein as a target server). Sometimes such copying is performed on a transaction by transaction basis. Consequently, failure of the source server will cause an instantaneous transition to the target server. Since the source server and the target server are identical or nearly identical, a user would not know that a transition has occurred.
Traditional replication operations are capable of duplicating, for example, a database file or volume at a binary level. Specifically, modifications to a source server database are made at a binary level and are subsequently replicated to a target server. One disadvantage associated with this technique is that there are no assurances that all of the data residing in a target server database is a reliable representation of the database existing on the source server. Notably, the database in the source server may become corrupted and ultimately replicated to the target server, thus compromising the integrity of the targeted database as well. Although there are programs that exist that attempt to repair a corrupted database, these utilities are not completely reliable. Furthermore, when database repair utilities are applied to large databases, the repair process can require an excessive amount of time, e.g., a 50 GB database may require eight hours to repair.
Thus, there is a need in the art for a more reliable method and apparatus for producing an uncorrupted database replica.